LMZ14201TZX-ADJ/NOPB [TI]
SIMPLE SWITCHER 6V to 42V, 1A Power Module in Leaded SMT-TO Package;型号: | LMZ14201TZX-ADJ/NOPB |
厂家: | TEXAS INSTRUMENTS |
描述: | SIMPLE SWITCHER 6V to 42V, 1A Power Module in Leaded SMT-TO Package 开关 |
文件: | 总29页 (文件大小:1870K) |
中文: | 中文翻译 | 下载: | 下载PDF数据表文档文件 |
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LMZ14201
SNVS649I –JANUARY 2010–REVISED OCTOBER 2015
®
LMZ14201 SIMPLE SWITCHER 6V to 42V, 1A Power Module in Leaded SMT-TO Package
1 Features
2 Applications
1
•
•
•
Integrated Shielded Inductor
Simple PCB Layout
•
Point of Load Conversions From 12-V and 24-V
Input Rail
•
•
Time-Critical Projects
Flexible Start-Up Sequencing Using External Soft-
Start and Precision Enable
Space Constrained and High Thermal
Requirement Applications
•
Protection Against Inrush Currents and Faults
Such as Input UVLO and Output Short Circuit
•
Negative Output Voltage Applications
(See AN-2027) SNVA425
•
•
–40°C to 125°C Junction Temperature Range
Single Exposed Pad and Standard Pinout for Easy
Mounting and Manufacturing
3 Description
The LMZ14201 SIMPLE SWITCHER® power module
is an easy-to-use step-down DC-DC solution that can
drive up to 1-A load with exceptional power
conversion efficiency, line and load regulation, and
output accuracy. The LMZ14201 is available in an
•
Fast Transient Response for Powering FPGAs
and ASICs
•
•
Low Output Voltage Ripple
Pin-to-Pin Compatible Family:
innovative
package
that
enhances
thermal
–
LMZ1420x (42 V Maximum 3 A, 2 A, 1 A)
performance and allows for hand or machine
soldering.
–
LMZ1200x (20 V Maximum 3 A, 2 A, 1 A)
•
•
Fully Enabled for WEBENCH® Power Designer
Electrical Specifications
The LMZ14201 can accept an input voltage rail
between 6 V and 42 V and deliver an adjustable and
highly accurate output voltage as low as 0.8 V. The
LMZ14201 only requires three external resistors and
four external capacitors to complete the power
solution. The LMZ14201 is a reliable and robust
design with the following protection features: thermal
shutdown, input UVLO, output overvoltage protection,
short-circuit protection, output current limit, and
allows start-up into a prebiased output. A single
resistor adjusts the switching frequency up to 1 MHz.
–
–
–
–
–
6-W Maximum Total Output Power
Up to 1-A Output Current
Input Voltage Range 6 V to 42 V
Output Voltage Range 0.8 V to 6 V
Efficiency up to 90%
•
Performance Benefits
–
–
–
–
Operates at High Ambient Temperature With
No Thermal Derating
Device Information(1)(2)
High Efficiency Reduces System Heat
Generation
PART NUMBER
PACKAGE
BODY SIZE (NOM)
LMZ14201
TO-PMOD (7)
10.16 mm × 9.85 mm
Low Radiated Emissions (EMI) Tested With
EN55022 Class B Standard
(1) For all available packages, see the orderable addendum at
the end of the data sheet.
Low External Component Count
(2) Peak reflow temperature equals 245°C. See SNAA214 for
more details.
Simplified Application Schematic
Efficiency 12-V Input at 25°C
100
LMZ14201
95
90
85
80
75
70
65
60
55
50
6.0
5.0
3.3
2.5
1.8
1.5
1.2
V
IN
V
OUT
C
R
ON
FF
0.8
R
FBT
Enable
R
COUT
FBB
C
C
SS
IN
25°C
0
0.2
0.4
0.6
0.8
1
OUTPUT CURRENT (A)
1
An IMPORTANT NOTICE at the end of this data sheet addresses availability, warranty, changes, use in safety-critical applications,
intellectual property matters and other important disclaimers. PRODUCTION DATA.
LMZ14201
SNVS649I –JANUARY 2010–REVISED OCTOBER 2015
www.ti.com
Table of Contents
1
2
3
4
5
6
Features.................................................................. 1
Applications ........................................................... 1
Description ............................................................. 1
Revision History..................................................... 2
Pin Configuration and Functions......................... 3
Specifications......................................................... 3
6.1 Absolute Maximum Ratings ...................................... 3
6.2 ESD Ratings.............................................................. 3
6.3 Recommended Operating Conditions....................... 4
6.4 Thermal Information.................................................. 4
6.5 Electrical Characteristics........................................... 4
6.6 Typical Characteristics ............................................. 6
Detailed Description ............................................ 11
7.1 Overview ................................................................. 11
7.2 Functional Block Diagram ....................................... 11
7.3 Feature Description................................................. 11
7.4 Device Functional Modes........................................ 12
8
Application and Implementation ........................ 13
8.1 Application Information............................................ 13
8.2 Typical Application .................................................. 13
Power Supply Recommendations...................... 19
9
10 Layout................................................................... 19
10.1 Layout Guidelines ................................................. 19
10.2 Layout Example .................................................... 21
10.3 Power Dissipation and Board Thermal
Requirements........................................................... 22
11 Device and Documentation Support ................. 23
11.1 Device Support...................................................... 23
11.2 Documentation Support ........................................ 23
11.3 Community Resources.......................................... 23
11.4 Trademarks........................................................... 23
11.5 Electrostatic Discharge Caution............................ 23
11.6 Glossary................................................................ 23
7
12 Mechanical, Packaging, and Orderable
Information ........................................................... 23
4 Revision History
NOTE: Page numbers for previous revisions may differ from page numbers in the current version.
Changes from Revision H (August 2015) to Revision I
Page
•
Added this new bullet in the Power Module SMT Guidelines section .................................................................................. 19
Changes from Revision G (May 2015) to Revision H
Page
•
Changed the title of the document ......................................................................................................................................... 1
Changes from Revision F (October 2013) to Revision G
Page
•
Added Pin Configuration and Functions section, ESD Rating table, Feature Description section, Device Functional
Modes, Application and Implementation section, Power Supply Recommendations section, Layout section, Device
and Documentation Support section, and Mechanical, Packaging, and Orderable Information section .............................. 1
Removed Easy-to-Use Pin Package image .......................................................................................................................... 1
Removed Evaluation Board Schematic Diagram and BOM section..................................................................................... 22
•
•
Changes from Revision E (March 2013) to Revision F
Page
•
•
•
•
•
Added Peak Reflow Case Temp = 245°C ............................................................................................................................. 1
Deleted 10 mils ...................................................................................................................................................................... 5
Changed 10 mils................................................................................................................................................................... 19
Added Power Module SMT Guidelines section.................................................................................................................... 19
Changed 10 mils................................................................................................................................................................... 22
2
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SNVS649I –JANUARY 2010–REVISED OCTOBER 2015
5 Pin Configuration and Functions
NDW Package
7-Pin TO-PMOD
Top View
VOUT
FB
SS
GND
EN
RON
VIN
7
6
5
4
3
2
1
Exposed Pad
Connect to GND
Pin Functions
PIN
TYPE
DESCRIPTION
NO.
NAME
1
VIN
Power
Supply input — Nominal operating range is 6 V to 42 V . A small amount of internal
capacitance is contained within the package assembly. Additional external input
capacitance is required between this pin and exposed pad.
2
3
RON
EN
Analog
Analog
On Time Resistor — An external resistor from VIN to this pin sets the ON-time of the
application. Typical values range from 25 kΩ to 124 kΩ.
Enable — Input to the precision enable comparator. Rising threshold is 1.18 V nominal;
90 mV hysteresis nominal. Maximum recommended input level is 6.5 V.
4
5
GND
SS
Ground
Analog
Ground — Reference point for all stated voltages. Must be externally connected to EP.
Soft-Start — An internal 8-µA current source charges an external capacitor to produce
the soft-start function. This node is discharged at 200 µA during disable, overcurrent,
thermal shutdown and internal UVLO conditions.
6
FB
Analog
Feedback — Internally connected to the regulation, overvoltage, and short-circuit
comparators. The regulation reference point is 0.8 V at this input pin. Connected the
feedback resistor divider between the output and ground to set the output voltage.
7
VOUT
EP
Power
Output Voltage — Output from the internal inductor. Connect the output capacitor
between this pin and exposed pad.
—
Ground
Exposed Pad — Internally connected to pin 4. Used to dissipate heat from the package
during operation. Must be electrically connected to pin 4 external to the package.
6 Specifications
6.1 Absolute Maximum Ratings
over operating free-air temperature range (unless otherwise noted)(1)(2)(3)
MIN
–0.3
–0.3
MAX
43.5
7
UNIT
V
VIN, RON to GND
EN, FB, SS to GND
Junction Temperature
Storage Temperature
V
150
150
°C
°C
–65
(1) Stresses beyond those listed under Absolute Maximum Ratings may cause permanent damage to the device. These are stress ratings
only, which do not imply functional operation of the device at these or any other conditions beyond those indicated under Recommended
Operating Conditions. Exposure to absolute-maximum-rated conditions for extended periods may affect device reliability.
(2) If Military/Aerospace specified devices are required, please contact the Texas Instruments Sales Office/ Distributors for availability and
specifications.
(3) For soldering specifications, see product folder at www.ti.com and SNOA549.
6.2 ESD Ratings
VALUE
UNIT
V(ESD)
Electrostatic discharge
Human body model (HBM), per ANSI/ESDA/JEDEC JS-001(1)
±2000
V
(1) JEDEC document JEP155 states that 500-V HBM allows safe manufacturing with a standard ESD control process.
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6.3 Recommended Operating Conditions
over operating free-air temperature range (unless otherwise noted)(1)
MIN
6
MAX
42
UNIT
V
VIN
EN
0
6.5
V
Operation Junction Temperature
−40
125
°C
(1) Absolute Maximum Ratings are limits beyond which damage to the device may occur. Recommended Operating Ratings are conditions
under which operation of the device is intended to be functional. For ensured specifications and test conditions, see the Electrical
Characteristics.
6.4 Thermal Information
LMZ14201
THERMAL METRIC(1)
NDW (TO-PMOD)
UNIT
7 PINS
19.3
21.5
1.9
4 layer JEDEC Printed Circuit Board, 100 vias, No air flow
2 layer JEDEC Printed Circuit Board, No air flow
Junction-to-ambient
thermal resistance
RθJA
°C/W
°C/W
RθJC(top)
Junction-to-case (top) thermal resistance
(1) For more information about traditional and new thermal metrics, see the Semiconductor and IC Package Thermal Metrics application
report, SPRA953.
6.5 Electrical Characteristics
Limits are for TJ = 25°C only unless otherwise noted. Minimum and Maximum limits are ensured through test, design or
statistical correlation. Typical values represent the most likely parametric norm at TJ = 25°C, and are provided for reference
purposes only. Unless otherwise stated the following conditions apply: VIN = 24 V, Vout = 3.3 V
PARAMETER
SYSTEM PARAMETERS
ENABLE CONTROL(3)
TEST CONDITIONS
MIN(1)
TYP(2)
MAX(1) UNIT
VEN
EN threshold trip point
VEN rising
1.18
V
over the junction temperature
(TJ) range of –40°C to +125°C
1.10
1.25
VEN-HYS
SOFT-START
ISS
EN threshold hysteresis
VEN falling
VSS = 0 V
90
8
mV
SS source current
µA
over the junction temperature
(TJ) range of –40°C to +125°C
5
11
ISS-DIS
SS discharge current
-200
1.95
µA
CURRENT LIMIT
ICL
Current limit threshold
DC average
A
3
over the junction temperature
(TJ) range of –40°C to +125°C
1.4
ON/OFF TIMER
tON-MIN
ON timer minimum pulse
width
150
260
ns
ns
tOFF
OFF timer pulse width
(1) Min and Max limits are 100% production tested at 25°C. Limits over the operating temperature range are ensured through correlation
using Statistical Quality Control (SQC) methods. Limits are used to calculate Average Outgoing Quality Level (AOQL).
(2) Typical numbers are at 25°C and represent the most likely parametric norm.
(3) EN 55022:2006, +A1:2007, FCC Part 15 Subpart B: 2007. See AN-2024 and layout for information on device under test.
4
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Electrical Characteristics (continued)
Limits are for TJ = 25°C only unless otherwise noted. Minimum and Maximum limits are ensured through test, design or
statistical correlation. Typical values represent the most likely parametric norm at TJ = 25°C, and are provided for reference
purposes only. Unless otherwise stated the following conditions apply: VIN = 24 V, Vout = 3.3 V
PARAMETER
TEST CONDITIONS
MIN(1)
TYP(2)
MAX(1) UNIT
REGULATION AND OVERVOLTAGE COMPARATOR
VFB
In-regulation feedback
voltage
VSS >+ 0.8 V
TJ = -40°C to
125°C
0.798
over the junction temperature
(TJ) range of –40°C to +125°C
V
.777
0.818
IO = 1 A
VSS > +0.8 V
TJ = 25°C
0.786
0.802
0.818
V
IO = 10 mA
VFB-OV
IFB
Feedback overvoltage
protection threshold
0.92
5
V
Feedback input bias
current
nA
mA
μA
IQ
Non Switching Input
Current
VFB= 0.86 V
VEN= 0 V
1
ISD
Shut Down Quiescent
Current
25
THERMAL CHARACTERISTICS
TSD
Thermal Shutdown
Rising
Falling
165
15
°C
°C
TSD-HYST
Thermal shutdown
hysteresis
PERFORMANCE PARAMETERS
ΔVO
Output Voltage Ripple
Line Regulation
Load Regulation
Efficiency
8
.01%
1.5
mV
PP
ΔVO/ΔVIN
ΔVO/IOUT
η
VIN = 12 V to 42 V, IO= 1 A
VIN = 24 V
mV/A
VIN = 24 V VO = 3.3 V IO = 1 A
92%
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6.6 Typical Characteristics
Unless otherwise specified, the following conditions apply: VIN = 24 V; CIN = 10 uF X7R Ceramic; CO = 100 uF X7R Ceramic;
TA = 25 C for efficiency curves and waveforms.
100
95
90
85
80
75
70
65
60
55
50
0.3
0.25
0.2
3.3
2.5
3.3
2.5
1.8
1.5
1.2
1.8
1.5
0.8
1.2
0.8
0.15
0.1
25°C
0.05
0
25°C
0
0.2
0.4
0.6
0.8
1
0.6
OUTPUT CURRENT (A)
0
1
0.2
0.4
0.8
OUTPUT CURRENT (A)
Figure 1. Efficiency 6-V Input at 25°C
Figure 2. Dissipation 6-V Input at 25°C
100
0.45
6.0
5.0
95
90
85
80
75
70
65
60
55
50
6.0
5.0
3.3
2.5
1.8
1.5
1.2
0.375
3.3
2.5
0.3
1.8
1.5
0.8
0.225
1.2
0.8
0.15
25°C
0.075
25°C
0
0
0.6
1
0.2
0.4
0.8
0
0.2
0.4
0.6
0.8
1
OUTPUT CURRENT (A)
OUTPUT CURRENT (A)
Figure 4. Dissipation 12-V Input at 25°C
Figure 3. Efficiency 12-V Input at 25°C
0.7
100
95
0.6
0.5
0.4
0.3
6.0
6.0
90
5.0
5.0
3.3
3.3
2.5
85
2.5
1.8
80
1.8
75
70
65
60
0.2
0.1
55
25°C
0
25°C
50
0
0.6
OUTPUT CURRENT (A)
1
0.2
0.4
0.8
0
0.2
0.4
0.6
0.8
1
OUTPUT CURRENT (A)
Figure 6. Dissipation 24-V Input at 25°C
Figure 5. Efficiency 24-V Input at 25°C
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Typical Characteristics (continued)
Unless otherwise specified, the following conditions apply: VIN = 24 V; CIN = 10 uF X7R Ceramic; CO = 100 uF X7R Ceramic;
TA = 25 C for efficiency curves and waveforms.
100
95
90
85
80
75
70
65
60
55
50
1.2
1.0
0.8
0.6
0.4
0.2
0
6.0
5.0
6.0
5.0
3.3
3.3
25°C
0.2
25°C
0.6
OUTPUT CURRENT (A)
0
0.4
0.6
0.8
1
0.2
0.4
0.8
1
0
OUTPUT CURRENT (A)
Figure 7. Efficiency 36-V Input at 25°C
Figure 8. Dissipation 36-V Input at 25°C
100
95
1.2
1.0
0.8
0.6
0.4
0.2
0
6.0
5.0
90
85
80
75
70
65
60
55
50
6.0
5.0
3.3
3.3
25°C
0.2
25°C
0
0.6
OUTPUT CURRENT (A)
1
0
0.4
0.6
0.8
1
0.2
0.4
0.8
OUTPUT CURRENT (A)
Figure 9. Efficiency 42-V Input at 25°C
Figure 10. Dissipation 42-V Input at 25°C
0.45
100
95
0.375
0.3
3.3
2.5
1.8
1.5
3.3
90
2.5
1.8
85
1.5
1.2
80
0.225
0.15
0.075
0
75
70
65
60
1.2
85°C
55
85°C
50
0
0.2
0.4
0.6
0.8
1
0
0.6
OUTPUT CURRENT (A)
1
0.2
0.4
0.8
OUTPUT CURRENT (A)
Figure 11. Efficiency 6-V Input at 85°C
Figure 12. Dissipation 6-V Input at 85°C
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Typical Characteristics (continued)
Unless otherwise specified, the following conditions apply: VIN = 24 V; CIN = 10 uF X7R Ceramic; CO = 100 uF X7R Ceramic;
TA = 25 C for efficiency curves and waveforms.
100
95
90
85
80
75
70
65
60
55
50
0.45
0.375
0.3
5.0
3.3
2.5
1.8
1.5
5.0
3.3
2.5
1.8
1.5
1.2
0.225
0.15
0.075
0
1.2
85°C
85°C
0
0.2
0.4
0.6
0.8
1
0.6
0
1
0.2
0.4
0.8
OUTPUT CURRENT (A)
OUTPUT CURRENT (A)
Figure 13. Efficiency 8-V Input at 85°C
Figure 14. Dissipation 8-V Input at 85°C
100
0.6
95
6.0
0.5
0.4
0.3
0.2
0.1
0
6.0
5.0
5.0
90
85
3.3
2.5
3.3
2.5
1.8
1.5
1.2
80
75
70
65
60
55
50
1.8
1.5
1.2
85°C
85°C
0.2
0.6
OUTPUT CURRENT (A)
0
0.4
0.8
0
0.2
0.4
0.6
0.8
1
1
OUTPUT CURRENT (A)
Figure 15. Efficiency 12-V Input at 85°C
Figure 16. Dissipation 12-V Input at 85°C
100
95
1.2
1.0
90
85
80
75
70
65
60
55
50
6.0
5.0
3.3
2.5
0.8
6.0
5.0
1.8
0.6
0.4
3.3
2.5
0.2
0
1.8
85°C
0.2
OUTPUT CURRENT (A)
85°C
0
0.4
0.6
0.8
1
0.6
0
0.2
0.4
0.8
1
OUTPUT CURRENT (A)
Figure 17. Efficiency 24-V Input at 85°C
Figure 18. Dissipation 24-V Input at 85°C
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Typical Characteristics (continued)
Unless otherwise specified, the following conditions apply: VIN = 24 V; CIN = 10 uF X7R Ceramic; CO = 100 uF X7R Ceramic;
TA = 25 C for efficiency curves and waveforms.
100
95
90
85
80
75
70
65
60
55
50
1.2
1.0
0.8
0.6
0.4
0.2
0
6.0
5.0
6.0
5.0
3.3
3.3
85°C
85°C
0.2
OUTPUT CURRENT (A)
0.6
OUTPUT CURRENT (A)
0
0.2
0.4
0.8
1
0
0.4
0.6
0.8
1
Figure 20. Dissipation 36-V Input at 85°C
Figure 19. Efficiency 36-V Input at 85°C
1.2
100
6.0
5.0
95
1.0
90
85
0.8
6.0
5.0
80
3.3
0.6
75
3.3
70
0.4
0.2
65
60
55
85°C
85°C
0
0
50
0.6
OUTPUT CURRENT (A)
1
0.2
0.4
0.8
0
0.2
0.4
0.6
0.8
1
OUTPUT CURRENT (A)
Figure 22. Dissipation 42-V Input at 85°C
Figure 21. Efficiency 42-V Input at 85°C
3.34
3.36
24
3.34
42
3.32
42
3.32
3.30
36
24
8
8
12 20
6
6
3.30
3.28
3.26
3.28
20
12
36
3.26
3.24
85°C
25°C
0
0.2
0.4
0.6
0.8
1.0
0.8
OUTPUT CURRENT (A)
1.0
0.4
0.6
0
0.2
OUTPUT CURRENT (A)
Figure 24. Line and Load Regulation at 85°C
Figure 23. Line and Load Regulation at 25°C
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Typical Characteristics (continued)
Unless otherwise specified, the following conditions apply: VIN = 24 V; CIN = 10 uF X7R Ceramic; CO = 100 uF X7R Ceramic;
TA = 25 C for efficiency curves and waveforms.
0.5 A/Div
20 mV/Div
200 Ps/Div
Figure 25. Output Ripple
24VIN 3.3 VO 1 A, BW = 200 MHz
Figure 26. Transient Response
24VIN 3.3 VO 0.5-A to 1-A Step
1.2
1
2.4
2.3
2.2
2.1
2.0
1.9
1.8
0.8
0.6
0.4
0.2
0
SHORT CIRCUIT
6V
IN
12V
IN
ONSET
ÆJA = 19°C/W
24V
IN
25°C
VOUT = 3.3V
36V
IN
0
5
10
15
20
25
50
70 80
90
60
100 110 120
AMBIENT TEMPERATURE (C)
INPUT VOLTAGE (V)
Figure 27. Thermal Derating VOUT = 3.3 V
Figure 28. Current Limit 1.8 VOUT at 25°C
2.4
2.5
2.3
2.4
SHORT CIRCUIT
SHORT CIRCUIT
2.3
2.2
2.1
2.2
ONSET
2.0
2.1
ONSET
1.9
2.0
25°C
1.8
0
85°C
1.9
30
INPUT VOLTAGE (V)
50
10
20
40
0
10
20
30
40
50
INPUT VOLTAGE (V)
Figure 29. Current Limit 3.3 VOUT at 25°C
Figure 30. Current Limit 3.3 VOUT at 85°C
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7 Detailed Description
7.1 Overview
7.1.1 COT Control Circuit Overview
Constant On Time control is based on a comparator and an ON-time one-shot, with the output voltage feedback
compared with an internal 0.8-V reference. If the feedback voltage is below the reference, the main MOSFET is
turned on for a fixed ON-time determined by a programming resistor RON. RON is connected to VIN such that ON-
time is reduced with increasing input supply voltage. Following this ON-time, the main MOSFET remains off for a
minimum of 260 ns. If the voltage on the feedback pin falls below the reference level again the ON-time cycle is
repeated. Regulation is achieved in this manner.
7.2 Functional Block Diagram
Vin
1
VIN
Linear reg
C
IN
Cvcc
5
SS
Css
ON
3
EN
0.47 PF
VOUT
R
7
2
6
RON
V
O
Timer
C
10 PH
FF
Co
FB
R
FBT
Internal
Passives
Regulator IC
R
FBB
GND
4
7.3 Feature Description
7.3.1 Output Overvoltage Comparator
The voltage at FB is compared to a 0.92-V internal reference. If FB rises above 0.92-V the ON-time is
immediately terminated. This condition is known as overvoltage protection (OVP). It can occur if the input voltage
is increased very suddenly or if the output load is decreased very suddenly. Once OVP is activated, the top
MOSFET ON-times will be inhibited until the condition clears. Additionally, the synchronous MOSFET will remain
on until inductor current falls to zero.
7.3.2 Current Limit
Current limit detection is carried out during the OFF-time by monitoring the current in the synchronous MOSFET.
Referring to the Functional Block Diagram, when the top MOSFET is turned off, the inductor current flows
through the load, the PGND pin and the internal synchronous MOSFET. If this current exceeds 2.0 A (typical) the
current limit comparator disables the start of the next ON-time period. The next switching cycle will occur only if
the FB input is less than 0.8V and the inductor current has decreased below 2.0 A. Inductor current is monitored
during the period of time the synchronous MOSFET is conducting. So long as inductor current exceeds 2.0 A,
further ON-time intervals for the top MOSFET will not occur. Switching frequency is lower during current limit due
to the longer OFF-time.
NOTE
Current limit is dependent on both duty cycle and temperature as illustrated in the graphs
in the Typical Characteristics section.
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Feature Description (continued)
7.3.3 Thermal Protection
The junction temperature of the LMZ14201 should not be allowed to exceed its maximum ratings. Thermal
protection is implemented by an internal Thermal Shutdown circuit which activates at 165 °C (typical) causing the
device to enter a low power standby state. In this state the main MOSFET remains off causing VO to fall, and
additionally the CSS capacitor is discharged to ground. Thermal protection helps prevent catastrophic failures for
accidental device overheating. When the junction temperature falls back below 145 °C (typical Hyst = 20 °C) the
SS pin is released, VO rises smoothly, and normal operation resumes.
Applications requiring maximum output current especially those at high input voltage may require application
derating at elevated temperatures.
7.3.4 Zero Coil Current Detection
The current of the lower (synchronous) MOSFET is monitored by a zero coil current detection circuit which
inhibits the synchronous MOSFET when its current reaches zero until the next ON-time. This circuit enables the
DCM operating mode, which improves efficiency at light loads.
7.3.5 Prebiased Start-Up
The LMZ14201 will properly start up into a prebiased output. This startup situation is common in multiple rail
logic applications where current paths may exist between different power rails during the startup sequence. The
following scope capture shows proper behavior during this event.
OUTPUT
VOLTAGE
3.3V OUTPUT
1.0 V/Div
2V PRE-BIAS
0.5 A/Div
OUTPUT
CURRENT
2.0 V/Div
1 ms/Div
ENABLE
Figure 31. Prebiased Start-Up
7.4 Device Functional Modes
7.4.1 Discontinuous Conduction and Continuous Conduction Modes
At light-load, the regulator operates in discontinuous conduction mode (DCM). With load currents above the
critical conduction point, it operates in continuous conduction mode (CCM). When operating in DCM the
switching cycle begins at zero amps inductor current; increases up to a peak value, and then recedes back to
zero before the end of the OFF-time. During the period of time that inductor current is zero, all load current is
supplied by the output capacitor. The next ON-time period starts when the voltage on the FB pin falls below the
internal reference. The switching frequency is lower in DCM and varies more with load current as compared to
CCM. Conversion efficiency in DCM is maintained because conduction and switching losses are reduced with
the smaller load and lower switching frequency.
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8 Application and Implementation
NOTE
Information in the following applications sections is not part of the TI component
specification, and TI does not warrant its accuracy or completeness. TI’s customers are
responsible for determining suitability of components for their purposes. Customers should
validate and test their design implementation to confirm system functionality.
8.1 Application Information
The LMZ14201 is a step-down DC-to-DC power module. It is typically used to convert a higher DC voltage to a
lower DC voltage with a maximum output current of 1 A. The following design procedure can be used to select
components for the LMZ14201. Alternately, the WEBENCH software may be used to generate complete designs.
When generating a design, the WEBENCH software uses iterative design procedure and accesses
comprehensive databases of components. For more details, go to www.ti.com.
8.2 Typical Application
U1
EP
V
IN
Enable
LMZ14201TZ-ADJ
3.3V @ 1A
O
6.0V to 42V
R
ENT
C
FF
0.022 PF
FBT
3.32k
68.1k
R
ON
R
61.9k
C
1
O
C 2
O
C
R
SS
C
2
C
1
FBB
IN
IN
R
ENB
1 PF
100 PF
0.022 PF
1.07k
D1
10 PF
1 PF
11.8k
OPT
Figure 32. Evaluation Board Schematic Diagram
Table 1. Schematic Bill of Materials
VOUT
5 V
RFBT
5.62 K
3.32 K
2.26 K
1.87 K
1 K
RFBB
1.07 K
1.07 K
1.07 K
1.50 K
1.13 K
8.45 K
39.2
RON
VIN RANGE
7.7...42 V
6...42 V
6...30 V
6...25 V
6...21 V
6...19 V
6...18 V
100 K
61.9 K
47.5 K
32.4 K
28 K
3.3 V
2.5 V
1.8 V
1.5 V
1.2 V
0.8 V
4.22 K
0
22.6 K
24.9 K
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Table 2. Bill of Materials
REF DES
U1
DESCRIPTION
SIMPLE SWITCHER ®
1 µF, 50V, X7R
10 µF, 50V, X7R
1 µF, 50V, X7R
100 µF, 6.3V, X7R
3.32 kΩ
CASE SIZE
PFM-7
1206
MANUFACTURER
Texas Instruments
Taiyo Yuden
Taiyo Yuden
Taiyo Yuden
Taiyo Yuden
Vishay Dale
Vishay Dale
Vishay Dale
Vishay Dale
Vishay Dale
TDK
MANUFACTURER P/N
LMZ14201TZ-ADJ
Cin1
UMK316B7105KL-T
UMK325BJ106MM-T
UMK316B7105KL-T
JMK325BJ107MM-T
CRCW06033K32FKEA
CRCW06031K07FKEA
CRCW060361k9FKEA
CRCW060368k1FKEA
CRCW060311k8FKEA
C1608X7R1H223K
C1608X7R1H223K
Optional
Cin2
1210
CO1
1206
CO2
1210
RFBT
RFBB
RON
RENT
RENB
CFF
0603
1.07 kΩ
0603
61.9 kΩ
0603
68.1 kΩ
0603
11.8 kΩ
0603
22 nF, ±10%, X7R, 16V
22 nF, ±10%, X7R, 16V
5.1V
0603
CSS
0603
TDK
D1
SOD-23
—
8.2.1 Design Requirements
For this example the following application parameters exist.
•
•
•
VIN Range = Up to 42 V
VOUT = 0.8 V to 5 V
IOUT = 1 A
Please refer to the table in Table 1 for more information.
8.2.2 Detailed Design Procedure
8.2.2.1 Design Steps for the LMZ14201 Application
The LMZ14201 is fully supported by WEBENCH and offers the following: Component selection, electrical and
thermal simulations as well as the build-it board for a reduction in design time. The following list of steps can be
used to manually design the LMZ14201 application.
1. Select minimum operating VIN with enable divider resistors
2. Program VO with divider resistor selection
3. Program turnon time with soft-start capacitor selection
4. Select CO
5. Select CIN
6. Set operating frequency with RON
7. Determine module dissipation
8. Lay out PCB for required thermal performance
8.2.2.1.1 Enable Divider, RENT and RENB Selection
The enable input provides a precise 1.18-V band-gap rising threshold to allow direct logic drive or connection to
a voltage divider from a higher enable voltage such as VIN. The enable input also incorporates 90 mV (typical) of
hysteresis resulting in a falling threshold of 1.09 V. The maximum recommended voltage into the EN pin is 6.5 V.
For applications where the midpoint of the enable divider exceeds 6.5 V, a small Zener diode can be added to
limit this voltage.
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The function of this resistive divider is to allow the designer to choose an input voltage below which the circuit
will be disabled. This implements the feature of programmable under voltage lockout. This is often used in
battery powered systems to prevent deep discharge of the system battery. It is also useful in system designs for
sequencing of output rails or to prevent early turnon of the supply as the main input voltage rail rises at power-
up. Applying the enable divider to the main input rail is often done in the case of higher input voltage systems
such as 24V AC/DC systems where a lower boundary of operation should be established. In the case of
sequencing supplies, the divider is connected to a rail that becomes active earlier in the power-up cycle than the
LMZ14201 output rail. The two resistors should be chosen based on the following ratio:
RENT / RENB = (VIN UVLO/ 1.18 V) – 1
(1)
The LMZ14201 demonstration and evaluation boards use 11.8 kΩ for RENB and 68.1 kΩ for RENT resulting in a
rising UVLO of 8 V. This divider presents 6.25 V to the EN input when the divider input is raised to 42 V.
The EN pin is internally pulled up to VIN and can be left floating for always-on operation.
8.2.2.1.2 Output Voltage Selection
Output voltage is determined by a divider of two resistors connected between VO and ground. The midpoint of
the divider is connected to the FB input. The voltage at FB is compared to a 0.8-V internal reference. In normal
operation an ON-time cycle is initiated when the voltage on the FB pin falls below 0.8 V. The main MOSFET ON-
time cycle causes the output voltage to rise and the voltage at the FB to exceed 0.8 V. As long as the voltage at
FB is above 0.8 V, ON-time cycles will not occur.
The regulated output voltage determined by the external divider resistors RFBT and RFBB is:
VO = 0.8V × (1 + RFBT / RFBB
)
(2)
(3)
Rearranging terms; the ratio of the feedback resistors for a desired output voltage is:
RFBT / RFBB = (VO / 0.8V) - 1
These resistors should be chosen from values in the range of 1.0 kΩ to 10.0 kΩ.
For VO = 0.8 V the FB pin can be connected to the output directly so long as an output preload resistor remains
that draws more than 20 µA. Converter operation requires this minimum load to create a small inductor ripple
current and maintain proper regulation when no load is present.
A feed-forward capacitor is placed in parallel with RFBT to improve load step transient response. Its value is
usually determined experimentally by load stepping between DCM and CCM conduction modes and adjusting for
best transient response and minimum output ripple.
A table of values for RFBT , RFBB , CFF, and RON is included in the applications schematic.
8.2.2.1.3 Soft-Start Capacitor Selection
Programmable soft-start permits the regulator to slowly ramp to its steady state operating point after being
enabled, thereby reducing current inrush from the input supply and slowing the output voltage rise-time to
prevent overshoot.
Upon turnon, after all UVLO conditions have been passed, an internal 8-µA current source begins charging the
external soft-start capacitor. The soft-start time duration to reach steady-state operation is given by the formula:
tSS = VREF × CSS / Iss = 0.8V × CSS / 8 µA
(4)
This equation can be rearranged as follows:
CSS = tSS × 8 μA / 0.8 V
(5)
Use of a 0.022-μF results in 2.2 ms soft-start interval which is recommended as a minimum value.
As the soft-start input exceeds 0.8 V the output of the power stage will be in regulation. The soft-start capacitor
continues charging until it reaches approximately 3.8V on the SS pin. Voltage levels between 0.8 V and 3.8 V
have no effect on other circuit operation. Note the following conditions will reset the soft-start capacitor by
discharging the SS input to ground with an internal 200-μA current sink.
•
•
•
•
The enable input being “pulled low”
Thermal shutdown condition
Overcurrent fault
Internal VCC UVLO (Approximately 4 V input to VIN)
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8.2.2.1.4 CO Selection
None of the required CO output capacitance is contained within the module. At a minimum, the output capacitor
must meet the worst-case minimum ripple current rating of 0.5 × ILR P-P, as calculated in Equation 20 below.
Beyond that, additional capacitance will reduce output ripple so long as the ESR is low enough to permit it. A
minimum value of 10 μF is generally required. Experimentation will be required if attempting to operate with a
minimum value. Ceramic capacitors or other low ESR types are recommended. See AN-2024 for more detail.
Equation 6 provides a good first pass approximation of CO for load transient requirements:
CO≥ISTEP*VFB × L × VIN/ (4 × VO × (VIN – VO) × VOUT-TRAN
)
(6)
Solving:
CO≥ 1 A × 0.8 V × 10 μH × 24 V / (4 × 3.3 V × ( 24 V – 3.3 V) × 33 mV) ≥ 21.3 μF
(7)
The LMZ14201 demonstration and evaluation boards are populated with a 100-uF 6.3-V X5R output capacitor.
Locations for other output capacitors are provided.
8.2.2.1.5 CIN Selection
The LMZ14201 module contains an internal 0.47 µF input ceramic capacitor. Additional input capacitance is
required external to the module to handle the input ripple current of the application. This input capacitance should
be very close to the module. Input capacitor selection is generally directed to satisfy the input ripple current
requirements rather than by capacitance value. Worst-case input ripple current rating is dictated by Equation 8:
I(CIN(RMS)) ≊ 1 / 2 × IO × √ (D / 1-D)
where
•
D ≊ VO / VIN
(8)
(As a point of reference, the worst-case ripple current will occur when the module is presented with full load
current and when VIN = 2 × VO).
Recommended minimum input capacitance is 10-uF X7R ceramic with a voltage rating at least 25% higher than
the maximum applied input voltage for the application. It is also recommended that attention be paid to the
voltage and temperature deratings of the capacitor selected. It should be noted that ripple current rating of
ceramic capacitors may be missing from the capacitor data sheet and you may need to contact the capacitor
manufacturer for this rating.
If the system design requires a certain minimum value of input ripple voltage ΔVIN be maintained then Equation 9
may be used.
CIN ≥ IO × D × (1–D) / fSW-CCM × ΔVIN
(9)
If ΔVIN is 1% of VIN for a 24-V input to 3.3-V output application this equals 240 mV and fSW = 400 kHz.
CIN≥ 1 A × 3.3 V / 24 V × (1– 3.3 V/24 V) / (400000 × 0.240 V)
≥ 0.9 μF
Additional bulk capacitance with higher ESR may be required to damp any resonant effects of the input
capacitance and parasitic inductance of the incoming supply lines.
8.2.2.1.6 RON Resistor Selection
Many designs will begin with a desired switching frequency in mind. For that purpose Equation 10 can be used.
f
SW(CCM) ≊ VO / (1.3 × 10-10 × RON
)
(10)
This can be rearranged as
R
ON ≊ VO / (1.3 × 10 -10 × fSW(CCM)
)
(11)
The selection of RON and fSW(CCM) must be confined by limitations in the ON-time and OFF-time for the COT
Control Circuit Overview section.
The ON-time of the LMZ14201 timer is determined by the resistor RON and the input voltage VIN. It is calculated
as follows:
tON = (1.3 × 10-10 × RON) / VIN
(12)
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The inverse relationship of tON and VIN gives a nearly constant switching frequency as VIN is varied. RON should
be selected such that the ON-time at maximum VIN is greater than 150 ns. The ON-timer has a limiter to ensure
a minimum of 150 ns for tON. This limits the maximum operating frequency, which is governed by Equation 13:
fSW(MAX) = VO / (VIN(MAX) × 150 ns)
(13)
This equation can be used to select RON if a certain operating frequency is desired so long as the minimum ON-
time of 150 ns is observed. The limit for RON can be calculated as follows:
R
ON ≥ VIN(MAX) × 150 nsec / (1.3 × 10 -10
)
(14)
If RON calculated in Equation 11 is less than the minimum value determined in Equation 14 a lower frequency
should be selected. Alternatively, VIN(MAX) can also be limited to keep the frequency unchanged.
NOTE
The minimum OFF-time of 260 ns limits the maximum duty ratio. Larger RON (lower FSW
)
should be selected in any application requiring large duty ratio.
8.2.2.1.6.1 Discontinuous Conduction and Continuous Conduction Mode Selection
Operating frequency in DCM can be calculated as follows:
2
f
SW(DCM) ≊ VO × (VIN-1) × 10 μH × 1.18 × 1020 × IO/(VIN–VO) × RON
(15)
In CCM, current flows through the inductor through the entire switching cycle and never falls to zero during the
OFF-time. The switching frequency remains relatively constant with load current and line voltage variations. The
CCM operating frequency can be calculated using Equation 7 above.
Figure 33 shows a comparison pair of waveforms of the showing both CCM (upper) and DCM operating modes.
The approximate formula for determining the DCM/CCM boundary is as follows:
IDCB ≊ VO × (VIN–VO) / (2 × 10 μH × fSW(CCM) × VIN)
(16)
Figure 34 shows a typical waveform showing the boundary condition.
500 mA/Div
2.00 Ps/Div
500 mA/Div
2.00 Ps/Div
Figure 34. Transition Mode Operation
VIN = 24 V, VO = 3.3 V, IO = 0.29 A
Figure 33. CCM and DCM Operating Modes
VIN = 12 V, VO = 3.3 V, IO = 1 A / 0.25 A
The inductor internal to the module is 10 μH. This value was chosen as a good balance between low and high
input voltage applications. The main parameter affected by the inductor is the amplitude of the inductor ripple
current (ILR). ILR can be calculated with:
ILR P-P = VO × (VIN– VO) / (10 µH × fSW × VIN)
where
•
VIN is the maximum input voltage and fSW is determined from Equation 10.
(17)
If the output current IO is determined by assuming that IO = IL, the higher and lower peak of ILR can be
determined. Be aware that the lower peak of ILR must be positive if CCM operation is required.
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8.2.3 Application Curves
100
95
90
85
80
75
70
65
60
55
50
1.2
1
0.8
0.6
0.4
0.2
0
0.4
0.6
0.8
1
0
0.2
50 60
70 80
90 100 110 120
OUTPUT CURRENT (A)
AMBIENT TEMPERATURE (°C)
Figure 35. Efficiency VIN = 24 V VOUT = 5.0 V
Figure 36. Thermal Derating Curve
VIN = 24 V, VOUT = 5.0 V
80.0
70.0
60.0
50.0
40.0
EN 55022 CLASS B LIMIT
30.0
20.0
10.0
0.0
0
1000
200
400
600
FREQUENCY (MHz)
800
Figure 37. Radiated Emissions (EN 55022 Class B)
from Evaluation Board
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9 Power Supply Recommendations
The LMZ14201 device is designed to operate from an input voltage supply range between 4.5 V and 42 V. This
input supply should be well regulated and able to withstand maximum input current and maintain a stable
voltage. The resistance of the input supply rail should be low enough that an input current transient does not
cause a high enough drop at the LMZ14201 supply voltage that can cause a false UVLO fault triggering and
system reset. If the input supply is more than a few inches from the LMZ14201, additional bulk capacitance may
be required in addition to the ceramic bypass capacitors. The amount of bulk capacitance is not critical, but a 47-
μF or 100-μF electrolytic capacitor is a typical choice.
10 Layout
10.1 Layout Guidelines
PCB layout is an important part of DC-DC converter design. Poor board layout can disrupt the performance of a
DC-DC converter and surrounding circuitry by contributing to EMI, ground bounce and resistive voltage drop in
the traces. These can send erroneous signals to the DC-DC converter resulting in poor regulation or instability.
Good layout can be implemented by following a few simple design rules.
1. Minimize area of switched current loops.From an EMI reduction standpoint, it is imperative to minimize
the high di/dt paths during PCB layout. The high current loops that do not overlap have high di/dt content that
will cause observable high-frequency noise on the output pin if the input capacitor (Cin1) is placed at a
distance away from the LMZ14201. Therefore place CIN1 as close as possible to the LMZ14201 VIN and
GND exposed pad. This will minimize the high di/dt area and reduce radiated EMI. Additionally, grounding for
both the input and output capacitor should consist of a localized top side plane that connects to the GND
exposed pad (EP).
2. Have a single point ground.The ground connections for the feedback, soft-start, and enable components
should be routed to the GND pin of the device. This prevents any switched or load currents from flowing in
the analog ground traces. If not properly handled, poor grounding can result in degraded load regulation or
erratic output voltage ripple behavior. Provide the single point ground connection from pin 4 to EP.
3. Minimize trace length to the FB pin.Both feedback resistors, RFBT and RFBB, and the feed forward
capacitor CFF, should be close to the FB pin. Because the FB node is high impedance, maintain the copper
area as small as possible. The trace are from RFBT, RFBB, and CFF should be routed away from the body of
the LMZ14201 to minimize noise.
4. Make input and output bus connections as wide as possible.This reduces any voltage drops on the input
or output of the converter and maximizes efficiency. To optimize voltage accuracy at the load, ensure that a
separate feedback voltage sense trace is made to the load. Doing so will correct for voltage drops and
provide optimum output accuracy.
5. Provide adequate device heat-sinking.Use an array of heat-sinking vias to connect the exposed pad to the
ground plane on the bottom PCB layer. If the PCB has a plurality of copper layers, these thermal vias can
also be employed to make connection to inner layer heat-spreading ground planes. For best results use a 6
× 6 via array with minimum via diameter of 8 mils thermal vias spaced 59 mils (1.5 mm). Ensure enough
copper area is used for heat-sinking to keep the junction temperature below 125°C.
10.1.1 Power Module SMT Guidelines
The recommendations below are for a standard module surface mount assembly
•
•
Land Pattern – Follow the PCB land pattern with either soldermask defined or non-soldermask defined pads
Stencil Aperture
–
For the exposed die attach pad (DAP), adjust the stencil for approximately 80% coverage of the PCB land
pattern
–
For all other I/O pads use a 1:1 ratio between the aperture and the land pattern recommendation
•
•
•
•
•
Solder Paste – Use a standard SAC Alloy such as SAC 305, type 3 or higher
Stencil Thickness – 0.125 to 0.15 mm
Reflow - Refer to solder paste supplier recommendation and optimized per board size and density
Refer to AN SNAA214 for Reflow information
Maximum number of reflows allowed is one
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Layout Guidelines (continued)
Figure 38. Sample Reflow Profile
Table 3. Sample Reflow Profile Table
MAX TEMP
(°C)
REACHED TIME ABOVE REACHED TIME ABOVE REACHED TIME ABOVE REACHED
PROBE
MAX TEMP
235°C
235°C
245°C
245°C
260°C
260°C
1
2
3
242.5
242.5
241.0
6.58
0.49
6.39
0.00
–
7.10
–
0.00
–
–
–
7.10
0.55
6.31
0.00
0.00
7.09
0.42
6.44
0.00
0.00
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10.2 Layout Example
V
IN
V
O
LMZ14201
VOUT
VIN
High
di/dt
C
in1
C
O1
GND
Loop 2
Loop 1
Figure 39. Minimize Area of Current Loops in Buck Module
Top View
Thermal Vias
GND
GND
EPAD
CIN
COUT
1
2
3
4
5
6
7
VOUT
VIN
RON
RFBT
RENT
RENB
CFF
CSS
RFBB
GND Plane
Figure 40. PCB Layout Guide
Figure 41. EVM Board Layout - Top View
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SNVS649I –JANUARY 2010–REVISED OCTOBER 2015
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Layout Example (continued)
Figure 42. EVM Board Layout - Bottom View
10.3 Power Dissipation and Board Thermal Requirements
For the design case of VIN = 24 V, VO = 3.3 V, IO = 1A, TAMB(MAX) = 85°C , and TJUNCTION = 125°C, the device
must see a thermal resistance from case to ambient of less than:
RθCA< (TJ-MAX – TAMB(MAX)) / PIC-LOSS – RθJC
(18)
Given the typical thermal resistance from junction to case to be 1.9 °C/W. Use the 85°C power dissipation curves
in the Typical Performance Characteristics section to estimate the PIC-LOSS for the application being designed. In
this application it is 0.52W.
RθCA = (125 — 85) / 0.52 W — 1.9 = 75
(19)
To reach RθCA = 75, the PCB is required to dissipate heat effectively. With no airflow and no external heat, a
good estimate of the required board area covered by 1 oz. copper on both the top and bottom metal layers is:
Board Area_cm2 = 500°C x cm2/W / RθJC
(20)
As a result, approximately 6 square cm of 1 oz copper on top and bottom layers is required for the PCB design.
Additional area will decrease die temperature proportionately. The PCB copper heat sink must be connected to
the exposed pad. Approximately thirty six, 8 mils thermal vias spaced 59 mils (1.5 mm) apart must connect the
top copper to the bottom copper. For an example of a high thermal performance PCB layout of approximately 31
square cm area. Refer to the Evaluation Board application note AN-2024 SNVA422. For more information on
thermal design see AN-2020 SNVA419 and AN-2026 SNVA424.
22
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Copyright © 2010–2015, Texas Instruments Incorporated
Product Folder Links: LMZ14201
LMZ14201
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SNVS649I –JANUARY 2010–REVISED OCTOBER 2015
11 Device and Documentation Support
11.1 Device Support
11.1.1 Third-Party Products Disclaimer
TI'S PUBLICATION OF INFORMATION REGARDING THIRD-PARTY PRODUCTS OR SERVICES DOES NOT
CONSTITUTE AN ENDORSEMENT REGARDING THE SUITABILITY OF SUCH PRODUCTS OR SERVICES
OR A WARRANTY, REPRESENTATION OR ENDORSEMENT OF SUCH PRODUCTS OR SERVICES, EITHER
ALONE OR IN COMBINATION WITH ANY TI PRODUCT OR SERVICE.
11.2 Documentation Support
11.2.1 Related Documentation
•
•
•
•
•
Design Summary LMZ1 and LMZ2 Power Modules, SNAA214
AN-2027 Inverting Application for the LMZ14203 SIMPLE SWITCHER Power Module, SNVA425
Evaluation Board Application Note AN-2024, SNVA422
AN-2020 Thermal Design By Insight, Not Hindsight, SNVA419
AN-2026 Effect of PCB Design on Thermal Performance of SIMPLE SWITCHER Power Modules, SNVA424
11.3 Community Resources
The following links connect to TI community resources. Linked contents are provided "AS IS" by the respective
contributors. They do not constitute TI specifications and do not necessarily reflect TI's views; see TI's Terms of
Use.
TI E2E™ Online Community TI's Engineer-to-Engineer (E2E) Community. Created to foster collaboration
among engineers. At e2e.ti.com, you can ask questions, share knowledge, explore ideas and help
solve problems with fellow engineers.
Design Support TI's Design Support Quickly find helpful E2E forums along with design support tools and
contact information for technical support.
11.4 Trademarks
E2E is a trademark of Texas Instruments.
WEBENCH, SIMPLE SWITCHER are registered trademarks of Texas Instruments.
All other trademarks are the property of their respective owners.
11.5 Electrostatic Discharge Caution
These devices have limited built-in ESD protection. The leads should be shorted together or the device placed in conductive foam
during storage or handling to prevent electrostatic damage to the MOS gates.
11.6 Glossary
SLYZ022 — TI Glossary.
This glossary lists and explains terms, acronyms, and definitions.
12 Mechanical, Packaging, and Orderable Information
The following pages include mechanical, packaging, and orderable information. This information is the most
current data available for the designated devices. This data is subject to change without notice and revision of
this document. For browser-based versions of this data sheet, refer to the left-hand navigation.
Copyright © 2010–2015, Texas Instruments Incorporated
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PACKAGE OPTION ADDENDUM
www.ti.com
3-Sep-2015
PACKAGING INFORMATION
Orderable Device
Status Package Type Package Pins Package
Eco Plan
Lead/Ball Finish
MSL Peak Temp
Op Temp (°C)
-40 to 125
Device Marking
Samples
Drawing
Qty
(1)
(2)
(6)
(3)
(4/5)
LMZ14201TZ-ADJ/NOPB
LMZ14201TZE-ADJ/NOPB
LMZ14201TZX-ADJ/NOPB
ACTIVE
TO-PMOD
TO-PMOD
TO-PMOD
NDW
7
7
7
250
Green (RoHS
& no Sb/Br)
CU SN
CU SN
CU SN
Level-3-245C-168 HR
Level-3-245C-168 HR
Level-3-245C-168 HR
LMZ14201
TZ-ADJ
ACTIVE
ACTIVE
NDW
NDW
45
Green (RoHS
& no Sb/Br)
-40 to 125
LMZ14201
TZ-ADJ
500
Green (RoHS
& no Sb/Br)
-40 to 125
LMZ14201
TZ-ADJ
(1) The marketing status values are defined as follows:
ACTIVE: Product device recommended for new designs.
LIFEBUY: TI has announced that the device will be discontinued, and a lifetime-buy period is in effect.
NRND: Not recommended for new designs. Device is in production to support existing customers, but TI does not recommend using this part in a new design.
PREVIEW: Device has been announced but is not in production. Samples may or may not be available.
OBSOLETE: TI has discontinued the production of the device.
(2) Eco Plan - The planned eco-friendly classification: Pb-Free (RoHS), Pb-Free (RoHS Exempt), or Green (RoHS & no Sb/Br) - please check http://www.ti.com/productcontent for the latest availability
information and additional product content details.
TBD: The Pb-Free/Green conversion plan has not been defined.
Pb-Free (RoHS): TI's terms "Lead-Free" or "Pb-Free" mean semiconductor products that are compatible with the current RoHS requirements for all 6 substances, including the requirement that
lead not exceed 0.1% by weight in homogeneous materials. Where designed to be soldered at high temperatures, TI Pb-Free products are suitable for use in specified lead-free processes.
Pb-Free (RoHS Exempt): This component has a RoHS exemption for either 1) lead-based flip-chip solder bumps used between the die and package, or 2) lead-based die adhesive used between
the die and leadframe. The component is otherwise considered Pb-Free (RoHS compatible) as defined above.
Green (RoHS & no Sb/Br): TI defines "Green" to mean Pb-Free (RoHS compatible), and free of Bromine (Br) and Antimony (Sb) based flame retardants (Br or Sb do not exceed 0.1% by weight
in homogeneous material)
(3) MSL, Peak Temp. - The Moisture Sensitivity Level rating according to the JEDEC industry standard classifications, and peak solder temperature.
(4) There may be additional marking, which relates to the logo, the lot trace code information, or the environmental category on the device.
(5) Multiple Device Markings will be inside parentheses. Only one Device Marking contained in parentheses and separated by a "~" will appear on a device. If a line is indented then it is a continuation
of the previous line and the two combined represent the entire Device Marking for that device.
(6) Lead/Ball Finish - Orderable Devices may have multiple material finish options. Finish options are separated by a vertical ruled line. Lead/Ball Finish values may wrap to two lines if the finish
value exceeds the maximum column width.
Important Information and Disclaimer:The information provided on this page represents TI's knowledge and belief as of the date that it is provided. TI bases its knowledge and belief on information
provided by third parties, and makes no representation or warranty as to the accuracy of such information. Efforts are underway to better integrate information from third parties. TI has taken and
Addendum-Page 1
PACKAGE OPTION ADDENDUM
www.ti.com
3-Sep-2015
continues to take reasonable steps to provide representative and accurate information but may not have conducted destructive testing or chemical analysis on incoming materials and chemicals.
TI and TI suppliers consider certain information to be proprietary, and thus CAS numbers and other limited information may not be available for release.
In no event shall TI's liability arising out of such information exceed the total purchase price of the TI part(s) at issue in this document sold by TI to Customer on an annual basis.
Addendum-Page 2
PACKAGE MATERIALS INFORMATION
www.ti.com
3-Sep-2015
TAPE AND REEL INFORMATION
*All dimensions are nominal
Device
Package Package Pins
Type Drawing
SPQ
Reel
Reel
A0
B0
K0
P1
W
Pin1
Diameter Width (mm) (mm) (mm) (mm) (mm) Quadrant
(mm) W1 (mm)
LMZ14201TZ-ADJ/NOPB
TO-
PMOD
NDW
NDW
7
7
250
500
330.0
24.4
10.6 14.22
5.0
16.0
24.0
Q2
LMZ14201TZX-ADJ/NOP
B
TO-
PMOD
330.0
24.4
10.6 14.22
5.0
16.0
24.0
Q2
Pack Materials-Page 1
PACKAGE MATERIALS INFORMATION
www.ti.com
3-Sep-2015
*All dimensions are nominal
Device
Package Type Package Drawing Pins
SPQ
Length (mm) Width (mm) Height (mm)
LMZ14201TZ-ADJ/NOPB
LMZ14201TZX-ADJ/NOPB
TO-PMOD
TO-PMOD
NDW
NDW
7
7
250
500
367.0
367.0
367.0
367.0
45.0
45.0
Pack Materials-Page 2
MECHANICAL DATA
NDW0007A
BOTTOM SIDE OF PACKAGE
TOP SIDE OF PACKAGE
TZA07A (Rev D)
www.ti.com
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